Creatine vs Citrulline: Which Pre-Workout Is Better?

Mike HartnettEvidence-Based

7+ years researching longevity protocols. Runs a 20+ supplement daily stack. Built CoreStacks after losing his father to heart disease.

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Creatine vs Citrulline at a Glance

What Is Creatine?

Creatine is a molecule your body makes naturally from three amino acids — arginine, glycine, and methionine. Your muscles store it as phosphocreatine, and when you need fast energy (sprinting, lifting, explosive movements), your cells use that phosphocreatine to regenerate ATP. Supplementing with creatine monohydrate saturates those stores so you have more fuel available for high-intensity work.

But here’s what most people miss: creatine isn’t just a gym supplement. The research on creatine has expanded way beyond bench press numbers. Studies show benefits for cognitive function, particularly under stress or sleep deprivation. There’s emerging data on neuroprotection. And the longevity community is paying attention — Peter Attia has discussed creatine supplementation on The Drive podcast, including its role in maintaining muscle mass (which he considers one of the strongest predictors of healthspan). Andrew Huberman has also covered creatine on the Huberman Lab podcast, noting benefits for both physical performance and brain function. For the full breakdown, see our creatine longevity guide.

The cost-to-benefit ratio is absurd. Creatine monohydrate runs $10–15/month for a clinical dose of 5 g/day. No loading phase required. No cycling needed. Just take it daily and let your stores saturate over 3–4 weeks. For product picks, check our best creatine supplements guide.

What Is Citrulline?

L-Citrulline is a non-essential amino acid found in watermelon (the name literally comes from citrullus, Latin for watermelon). Your body converts citrulline to arginine in the kidneys, which then gets used to produce nitric oxide — the molecule that relaxes blood vessel walls and increases blood flow. More blood flow means better oxygen delivery, better nutrient transport, and yes, bigger muscle pumps.

Citrulline malate is the more common supplement form — it’s L-citrulline bonded to malic acid (a Krebs cycle intermediate). The malate component may offer its own mild fatigue-reduction benefits, though the evidence for that piece is thin. Most of the performance benefits come from the citrulline side of the molecule.

The research is decent but not spectacular. A 2010 study in the British Journal of Sports Medicine found citrulline malate reduced muscular fatigue and increased ATP production during exercise. A few trials show modest improvements in reps to failure (typically 1–2 extra reps on the last set). It’s a fine pre-workout ingredient. But “fine” is about where it tops out.

Key Differences Between Creatine and Citrulline

Completely Different Energy Systems

This is the fundamental distinction. Creatine works on the phosphocreatine system — it regenerates ATP for short, explosive efforts (think heavy lifts, sprints, anything under 10 seconds of max effort). Citrulline works on blood flow via nitric oxide — it improves oxygen and nutrient delivery during sustained efforts. They’re not competing. They’re addressing different metabolic pathways entirely. Creatine fuels the engine. Citrulline widens the pipes.

The Research Gap Is Massive

Look, there’s no polite way to put this. Creatine has been studied in over 500 peer-reviewed papers. It’s the most researched ergogenic supplement in history. The International Society of Sports Nutrition has published position stands calling it safe and effective. Citrulline has maybe 30–40 decent trials, most with small sample sizes and modest effect sizes. Both are “evidence-based,” but the depth of evidence isn’t remotely comparable. For an overview of how creatine fits into longevity science, our creatine for brain health article covers the cognitive angle.

Benefits Beyond the Gym

Creatine has a whole second life outside of exercise performance. The brain data is real — improved working memory under stress, potential neuroprotective effects, benefits for sleep-deprived cognition. There’s even preliminary research on creatine and traumatic brain injury recovery. Citrulline’s benefits outside the gym are limited to mild blood pressure reduction in some populations (via the nitric oxide pathway). If you’re evaluating these purely as performance supplements, the gap narrows. If you’re evaluating them as health supplements, creatine runs away with it. See our guide to creatine safety over 40 for age-specific considerations.

Cost and Simplicity

Creatine monohydrate: 5 g/day, any time, with anything, $10–15/month. Citrulline malate: 6–8 g pre-workout (timing matters), $15–25/month. Creatine is cheaper and simpler to use. No timing window, no need to pair with a workout. Citrulline only really makes sense if you take it 30–60 minutes before training. For a wider look at supplement costs across expert-recommended stacks, see our longevity stack cost breakdown.

Can You Stack Creatine and Citrulline?

Yes, and this is actually a solid combination. Since they work through completely different pathways, there’s no redundancy and no conflict. Creatine tops off your ATP reserves for heavy sets. Citrulline improves blood flow and oxygen delivery during your workout. Many well-formulated pre-workouts include both for exactly this reason.

If you’re going to stack them, take your creatine daily (timing doesn’t matter) and your citrulline 30–60 minutes pre-workout. No interaction concerns. Use our supplement interaction checker to verify compatibility with the rest of your stack. The one caveat: don’t pay for a fancy pre-workout that underdoses both. Buy them separately and dose them properly.

What Experts Say

Andrew Huberman has discussed creatine extensively on the Huberman Lab podcast, recommending 5 g/day of creatine monohydrate for both physical and cognitive benefits. He’s cited the brain health data with genuine enthusiasm. His full supplement approach is detailed in our Huberman supplement stack breakdown. He has not, to my knowledge, specifically championed citrulline.

Peter Attia considers maintaining muscle mass one of the most important levers for longevity, and creatine supports that directly. He’s discussed creatine on The Drive podcast in the context of resistance training and sarcopenia prevention. His broader longevity framework is in our Attia protocol breakdown.

Brad Stanfield has reviewed creatine’s evidence base on YouTube and includes it in his own protocol. He’s noted that creatine monohydrate is one of the few supplements where the evidence is essentially bulletproof. See our Stanfield protocol page for his full stack. No major longevity or health expert has made a strong case for citrulline as a must-have supplement.

Which Should You Choose?

Go with creatine if you:

• Want the single most evidence-backed performance supplement available
• Care about strength, power output, and muscle recovery
• Want cognitive benefits on top of physical ones — see our creatine and brain health breakdown
• Want the cheapest effective supplement on the market ($10–15/month)
• Train with any kind of resistance or high-intensity exercise
• Are over 40 and concerned about muscle preservation — check creatine safety for 40+

Go with citrulline if you:

• Specifically want better muscle pumps and vascularity during training
• Do endurance-style training (high-rep sets, circuits, longer sessions)
• Want to improve exercise performance in the 1–3 minute effort range
• Already take creatine and want to add a complementary pre-workout ingredient

My take: I take creatine monohydrate every single day. 5 grams in my morning water. Have for years. It’s the first supplement I’d recommend to literally anyone who trains. Citrulline? I’ll throw it in my pre-workout on heavy training days for the pump and blood flow, but if I had to drop one tomorrow, citrulline goes without a second thought. The gap between these two isn’t a gap — it’s a canyon. For how creatine compares to other performance supplements, see our creatine vs beta-alanine comparison and creatine vs taurine breakdown.

Frequently Asked Questions

This article is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement regimen.